#include<stdio.h>
#define MONTHS 12
#define YEARS 5
int main(void)
{
     double rain[YEARS][MONTHS]=
     {
          {4.3,4.3,4.3,3.0,2.0,1.2,0.2,0.2,0.4,2.4,3.5,6.6},
          {8.5,8.2,1.2,1.6,2.4,0.0,5.2,0.9,0.3,0.9,1.4,7.3},
          {9.1,8.5,6.7,4.3,2.1,0.8,0.2,0.2,1.1,2.3,6.1,8.4},
          {7.2,9.9,8.4,3.3,1.2,0.8,0.4,0.0,0.6,1.7,4.3,6.2},
          {7.6,5.6,3.8,2.8,3.8,0.2,0.0,0.0,0.0,1.3,2.6,5.2}
     };
     int year,month;
     double subtot,total;
     double (*ptr)[12];
     ptr=rain;
     
     printf(" YEAR   RAINFALL (inches) \n");
     for(year = 0,total = 0;year<YEARS;year++)
     {
          for(month=0,subtot=0;month<MONTHS;month++)
          {
              subtot+=(**ptr);
               (*(ptr+year))++;
          }
          printf("%5d   %15.1f\n",2000+year,subtot);
          total+=subtot;
     }
    printf("\nThe yearly average is %.1f inches.\n\n",total/YEARS);
     printf("MONTHLY AVERAGES: \n\n");
     printf(" Jan Feb Mar Apr May Jun Jul Aug Sep OCT ");
     printf(" Nov Dec\n");
     
     for(month=0;month<MONTHS;month++)
     {
          for(year=0,subtot=0;year<YEARS;year++)
          {
               subtot+=(**ptr);
               (*(ptr+year)+month)++;
          }
          printf("%4.1f",subtot/YEARS);
     }
     printf("\n");
     return 0;
}
为什么(*(ptr+year))++;和这个(*(ptr+year)+month)++;都是错的

[ 本帖最后由 lc5491137 于 2012-4-17 16:09 编辑 ]

这是改完的，你自己对照着看吧，祝你好运。
#include<stdio.h>
 #define MONTHS 12
 #define YEARS 5
 int main(void)
 {
      double rain[YEARS][MONTHS]=
      {
           {4.3,4.3,4.3,3.0,2.0,1.2,0.2,0.2,0.4,2.4,3.5,6.6},
           {8.5,8.2,1.2,1.6,2.4,0.0,5.2,0.9,0.3,0.9,1.4,7.3},
           {9.1,8.5,6.7,4.3,2.1,0.8,0.2,0.2,1.1,2.3,6.1,8.4},
           {7.2,9.9,8.4,3.3,1.2,0.8,0.4,0.0,0.6,1.7,4.3,6.2},
           {7.6,5.6,3.8,2.8,3.8,0.2,0.0,0.0,0.0,1.3,2.6,5.2}
      };
      int year,month;
      double subtot,total;
      double (*ptr)[12];
      double *a[5];
      
      printf(" YEAR   RAINFALL (inches) \n");
      for(year = 0,total = 0;year<YEARS;year++)
      {
          ptr=rain;
           for(month=0,subtot=0;month<MONTHS;month++)
           {
               subtot+=*(*(ptr+year)+month);
           }
           printf("%5d   %15.1f\n",2000+year,subtot);
           total+=subtot;
      }
     printf("\nThe yearly average is %.1f inches.\n\n",total/YEARS);
      printf("MONTHLY AVERAGES: \n\n");
      printf(" Jan   Feb   Mar   Apr   May  Jun   Jul   Aug   Sep   OCT ");
      printf("  Nov  Dec\n");
      
      for(month=0,subtot=0;month<MONTHS;month++)
      {
        
           for(year=0,subtot=0;year<YEARS;year++)
           {
               a[year]=rain[year];
               subtot+=*(*(a+year)+month);
           }
           printf("%4.1f  ",subtot/YEARS);
      }
      printf("\n");
      return 0;
 }
  

[ 本帖最后由 heyufeng493 于 2012-4-17 16:39 编辑 ]

同学：这里指的是多维数组，只是这里
subtot+=**ptr;
(*(ptr+year))++和下面for循环中同样的有问题而已

2L是改完的，我运行了，结果也正确，你还有什么要说的。

我早知道正确答案了，我想知道的是为什么
subtot += *(*(ptr + year) + month);不能被替换成
subtot+=(**ptr);
(*(ptr+year))++;

并且subtot += *(*(ptr + year) + month);不能替换成
subtot+=(**ptr);
(*(ptr+year)+month)++;

[ 本帖最后由 lc5491137 于 2012-4-17 17:51 编辑 ]

开始定义的double (*ptr)[12]；这是数组指针，基类型是“行”，而且他只是一个指针，不是12个指针，而且每次移动必须移动一行，subtotal+=（*ptr)这个没问题，但是（*（ptr+year)）++这里就不行了，你可能是想让他每次移动8个字节（double)，但是数组指针自增就 表示移动一行。